DE29706098U1 - Carriage drive device - Google Patents

Abstract

A slide drive device has a principal housing, in which at least one actuating element able to be driven linearly is arranged. Externally on the principal housing there is a slide kinetically coupled with the actuating element. Two stroke limiting means render possible a variable preset of the two end positions of the slide and each comprise an adjustable arranged on the one part and a counter-abutment arranged opposite to same on the other part. The one adjustable abutment is arranged on the slide and the other adjustable abutment is located on the principal housing. Both abutments are provided in end regions facing in the same axial direction, on the slide and, respectively, on the principal housing.

Description

G 17 886 - lens 20 March 1997

Festo KG, 73734 Esslingen Carriage drive device

The invention relates to a carriage drive device, with a base housing in which at least one actuating element that can be driven to perform a linear movement is arranged, with a carriage arranged on the outside of the base housing, coupled in motion to the at least one actuating element, which is guided by a guide device relative to the base housing so that it can move linearly between two end positions, and with two stroke limiting devices acting between the base housing and the carriage for variably specifying the two end positions of the carriage, each of which comprises a stop arranged on one part, adjustable in the direction of movement of the carriage, and a counter stop arranged opposite this on the other part.

A slide drive device of this type is disclosed, for example, in EP 0 683 010 A1. Its base housing contains one or more actuating elements designed as pistons, which are connected via a piston rod to a piston rod mounted on the outside of the base housing.

are coupled in terms of movement by means of a slidingly guided slide. The slide is designed to be coupled to a component to be moved and can be driven to a reciprocating linear movement by applying pressure to the pistons. Two stroke limiting devices are provided to specify the two end positions of the slide, each of which has an adjustable stop that works together with a fixed counter-stop. The two adjustable stops are arranged at the opposite end areas of the slide, while a common counter-stop sits between the stops and is fixed to the base housing.

A disadvantage of the known arrangement is that the working area of the slide drive device must be manipulated in order to set the stop that specifies the retracted end position. Apart from the resulting dangerous situations, this also causes problems with handling, since objects to be moved are usually attached to the top or front of the slide, which can impair accessibility to the stop.

Similar deficiencies also arise in EP 0 603 459 A2, which describes a similar carriage drive device.

The invention is therefore based on the object of creating a carriage drive device of the type mentioned at the beginning, in which

which allows a safer and more user-friendly adjustment of the end positions of the slide.

To solve this problem, it is provided that one adjustable stop is arranged on the slide and the other adjustable stop is arranged on the base body, whereby both adjustable stops are provided on end regions of the slide or the base housing pointing in the same axial direction.

This creates a slide drive device in which both adjustable stops are accessible from a common axial side, whereby this axial side is usually the rear of the slide drive device. In comparison to the state of the art, one adjustable stop is arranged on the base body and can therefore be provided on the end area to which the adjustable stop arranged on the slide is assigned. The settings for both end positions can therefore be made very precisely from a common side.

EP 0 603 459 A2 does indeed already describe an embodiment in which the adjustable stops are arranged in close proximity to one another. However, they are still both located on the movable carriage and in the area of one long side of the base housing, so that making adjustments is still cumbersome, especially since the manipulations required for the adjustments still have to be carried out on the stops from opposite sides.

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Advantageous further developments of the invention emerge from the subclaims.

The slide expediently has an open recess on the front side at its end area facing the adjustable stop fixed to the base housing, into which the stop can be inserted when the slide moves into the end position specified by it. The stop can therefore be arranged within the outline of the base housing and does not protrude outwards in a disruptive manner.

In a corresponding manner, the slide can also have a recess at the end for the adjustable stop arranged on it, into which the stop can protrude, in particular with its actuating part which is to be handled for adjustment.

It is also advantageous if the two stroke limiting devices are arranged laterally on both sides of the guide device extending in the longitudinal direction, whereby they can be provided in the area of the two opposite longitudinal sides if the carriage drive device is designed accordingly.

The adjustable stops can be formed by stop bodies that have an external thread and are screwed into an associated complementary threaded hole of a holding part provided on the slide or on the base body. By turning the stop body, an adjustment movement can be made in

The direction of movement of the slide can be achieved and the desired end position can be set. A lock nut can help to securely fix the set end position.

The adjustable stops can be formed by simple screws, for example. The stop body can also be the housing of a fluidic shock absorber, which is designed to dampen the impact of the slide when it reaches the assigned end position. In this case, the adjustable stop and the associated shock absorber can be designed as a structural unit. The latter has the advantage that the damping stroke is independent of the stop setting and always remains the same.

The invention is explained in more detail below with reference to the accompanying drawings, in which:

Figure 1 shows a preferred design of the carriage drive device in perspective view with a view of the rear side,

Figure 2 is a schematic side view of the carriage drive device from Figure 1 looking in the direction of arrow II, and

Figure 3 shows a longitudinal section through the carriage drive device viewed from above along section line III-III in Figures 1 and 2.

The carriage drive device 1 shown in the drawing comprises an elongated base housing 2 and a carriage 4 guided thereon so as to be displaceable back and forth in the longitudinal direction according to the double arrow 3.

The base housing 2 has two housing chambers 5 arranged at a distance from one another in the longitudinal direction 9, in each of which an axially movable piston 6 is arranged. The piston 6 divides the associated housing chamber 5 into two working spaces 7, 8 under sealing, which communicate with pressure medium channels 12, 13 indicated schematically in Figure 2, which open out on the outside of the base housing 2. Preferably, the corresponding openings are located on a common front side of the base housing 2, for example on the rear front side 14. A fluid pressure medium, in particular compressed air, can be supplied and discharged as required via pressure medium lines that can be connected to the openings in order to cause the piston 6 to move linearly in one direction or the other. Since all pressure medium connections are located together on the rear face 14, connecting the pressure medium lines is very easy and it is prevented that they collide with the moving carriage 4 during operation.

A piston rod 15 is attached to each piston 6, which protrudes from the base housing 2 at the front end face 16. In Figure 2, only one of the piston rods 15 is visible, the other piston rod is concealed and lies behind it.

The piston rods 15 are attached to the slide 4 outside the base housing 2. In this way, the slide 4 is axially coupled to the pistons 6 forming the actuating elements 17. The displacement of the actuating elements 17 causes a simultaneous displacement of the slide 4 in the already mentioned displacement direction 3.

In order to guide the carriage 4 safely during its linear movement and to support it in the transverse direction, a guide device 18 is interposed between it and the base housing 2. In the exemplary embodiment, this comprises a first guide rail 22, which is arranged on the outside of the base housing 2 and extends in its longitudinal direction 9. The relevant outside is referred to below as the top side 23. The length of the first guide rail 22 expediently corresponds essentially to that of the base housing 2.

The base housing 2 is flattened in the area of the top side 23. This is achieved by the base housing 2 having an essentially rectangular outer contour when viewed in cross section. The plane in which the two housing chambers 5 are contained runs parallel to the extension plane of the top side 23. The first guide rail 22 is expediently arranged centrally in relation to the width of the top side 23, which is also clearly visible in Figure 3.

The guide device 18 also has two second guide rails 24, which are arranged on both sides of the first guide rail 22. These second guide rails

Guide rails 24 are fixed by screws or other fastening means 25 to the underside of a plate-like first slide section 26, which extends axially over the base housing 2 in the area of the top side 23.

In the embodiment, the slide 4 has an overall approximately L-shaped configuration, with one of the L-legs being formed by the first slide section 26. This first slide section 26 projects beyond the front end face 16 of the base housing 2, with a second slide section 27 adjoining there, which projects downwards in front of the said front end face 16 and forms the other L-leg. The piston rods 15 are fixed to the second slide section 27.

The guide device 18 of the embodiment is designed as a rolling guide. As shown, it can comprise two groups of a plurality of, for example, spherical rolling elements 28, which are held in a guide cage 32 and are interposed between the first guide rail 22 and the two second guide rails 24. The guide rails 22, 24 have longitudinal guide grooves 31 on the long sides facing each other, which complement each other in pairs to form a guide channel in which the rolling elements 28 are located. If the carriage 4 is displaced relative to the base housing 2, the rolling elements 23 run along the guide grooves 32 and thus ensure low-friction and extremely precise longitudinal guidance.

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It goes without saying that a sliding guide can also be used instead of a roller guide. Furthermore, instead of the multiple arrangement of piston and piston rod shown, a single arrangement could also be provided. The slide drive device could also be electrically operated, whereby the actuating element 17 could be a part provided with a thread that runs along a spindle driven by an electric motor.

When the slide drive device 1 is used, a component that can be moved linearly is arranged on the slide 4, which is indicated in Figure 2 by dash-dotted lines at 33. The component 33 could easily be the base housing 2 of another slide drive device 1 that is aligned at right angles so that multi-coordinate positioning can be carried out. Such use occurs particularly in handling technology. The component 33 is usually fixed to the top side 34 of the first slide section 26 facing away from the base housing 2 or to the front side 35 of the second slide section 27 facing away from the front face 16.

The slide drive device 1 is further equipped with two stroke limiting devices 36, 37, by means of which the stroke, i.e. the travel path of the slide 4 relative to the base housing 2, can be limited by specifying the two axial end positions of the slide 4. The one end position shown in Figures 1 and 3 represents the retracted position of the slide 4, in which it

its first slide section 26 axially overlaps as much as possible and covers the top 23 of the base housing 2, for example, at least approximately over the entire length. The piston rods 15 are retracted into the base housing 2. If pressure medium is supplied, the piston rods 15 extend, whereby the slide 4 is displaced forwards while reducing the degree of overlap until it reaches the second end position, which shall be referred to as the extended position.

Of the two stroke limiting devices 36, 37, one (36) is intended to specify the retracted position and the other (37) to specify the extended position. Both end positions can be variably adjusted independently of one another.

The first stroke limiting device 36 responsible for the retracted position has a stop 38 arranged on the base housing 2 that is axially adjustable in the displacement direction 3 of the slide 4. It is referred to as the first adjustable stop 38. Opposite it in the displacement direction 3 towards the front is a non-adjustable first counter stop 3 9 provided on the slide 4.

The second stroke limiting device 37 responsible for the extended position has a second adjustable stop 38', which is arranged on the slide 4 so that it can be adjusted relative to it in the direction of displacement 3. A second counter stop 39' arranged on the base housing 2 is axially opposite it in the direction of displacement 3 towards the front.

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The two adjustable stops 38, 38' are advantageously located on end regions 42, 43 of the base housing 2 or the slide 4 pointing in the same axial direction. In the exemplary embodiment, these are the rear end regions 42, 43 of the relevant parts arranged opposite to the second slide section 27. The arrangement can be such that the two adjustable stops 38, 38' are jointly assigned to the end region 42 of the base housing 2 when the slide 4 is in the retracted position and are essentially at the same height with respect to the direction of displacement 3. The arrangement ensures simple and clear setting of the desired end position from the rear of the slide drive device 1 and without interference from components 33 fixed to the slide 4.

Preferably, the two stroke limiting devices 36, 37 are located on either side of the central guide device 18, so that mutual interference with handling and functionality is excluded.

The two stroke limiting devices 36, 37 are described in more detail below.

The first stroke limiting device 36, which determines the retracted position of the slide 4, comprises an upwardly projecting holding part 44 provided on the rear end area 42 of the base housing 2 on its upper side 23. This can be an integral part of the base housing 2. In the embodiment, it has a block-like shape. It serves to

Mounting of the first adjustable stop 38, which in the embodiment has a stop body 46 provided with an external thread 45, which is screwed into a threaded hole 47 that passes through the holding part 44 in the longitudinal direction 9. The stop body 46 is an elongated part and has a tool gripping section 48 on its rear side facing backwards, which enables the attachment of a screwing tool. The latter is designed as an internal polygon, for example, but the stop body 46 could also be designed as a simple screw with a head.

The stop body 46 passes through the threaded hole 47 and protrudes from the front of the holding part 44 with a stop section 52. By turning the stop body 46, which results in an axial displacement, the axial position of the stop section 52 can be adjusted relative to the base housing 2. To releasably secure the setting, a locking element 53 can be present, which is formed, for example, by a lock nut sitting on the external thread 45 and which can be clamped against the holding part 44.

The slide 4 has a recess 54 on its rear end area 42 on the side of the first stroke limiting device 36, which is open at the front towards the rear. Its axial length corresponds approximately to the length of the distance between the front of the holding part 44 associated with the stop section 52 and the rear end face 14 of the base housing 2. The recess 54 is also expediently open at the side, so that a wall only extends inwards towards the guide device 18.

40 of the carriage 4 remains. If the carriage 5 is in the retracted position according to Figures 1 and 3, the first adjustable stop 38 including the associated holding part 44 is in particular completely immersed in the recess 54. The arrangement has the advantage that the central area 55 of the first carriage section 26 associated with the guide device 18, which flanks the recess 54 on the inside, can have a large length independent of the design of the first stroke limiting device 3 6, so that even when the carriage 4 is extended far, there is still a secure, long guide contact between the guide rails 22, 24.

The counter stop 39, which interacts with the first adjustable stop 38, is arranged on the facing end region 42 of the slide and is located on the end part 51 of the first slide section 26 which axially limits the recess 54 towards the front. It can be formed directly by the slide 4 or, as in the exemplary embodiment, by a counter stop body 56 arranged on the chute 4. In the exemplary embodiment, this counter stop body 56 is designed like a pot and is inserted and in particular pressed into an axial recess 57 of the slide 4. A circumferential collar lying outside the axial recess 57 forms a counter stop part 58 which runs onto the stop part 52 when the retracted position is reached.

In order to mitigate the final impact, a buffer element 59 can also be provided, the effect of which occurs before the assigned end position is reached. It consists, for example, of

Material with rubber-elastic properties and can be inserted into the recess 62 of the counter-stop body 56, which is open towards the stop body 46, in such a way that it normally protrudes a little beyond the counter-stop section 58 towards the stop section 52. In this way, the buffer element 59 hits the stop section 52 in front of the counter-stop section 58 and is then elastically deformed until there is contact between the counter-stop section 58 and the stop section 52. An edge-side cross-sectional expansion 63 in the recess 62 ensures the deformation of the incompressible buffer material.

The second adjustable stop 38' of the second stroke limiting device 37, which is arranged on the opposite long side and serves to specify the extended position, is designed in a similar way to the first adjustable stop 38 in terms of the type of fastening and adjustment. It is arranged on a holding part 44' which is firmly connected to the first slide section 26 and has an axially continuous threaded bore 47' through which the associated stop body 46' is screwed. The holding part 44' is expediently an integral part of the slide 4. When viewed with the slide 4 retracted, it is preferably located axially a little way inside the rear end face 14 of the base housing 2 and delimits a recess 54' towards the front which is open towards the rear end face of the slide 4. The recess 54' serves to accommodate the rear end section 64 of the stop body 46', which projects beyond the holding part 44' at the rear.

The rear recess 54' is also open at the side, i.e. both to the side outside and upwards, so that the actuating part of the stop body provided with the tool engagement part 48' and formed by the end section 64 as well as the securing element 53, 53' are easily accessible.

The setting and securing of the position of the stop body 46' corresponds to that of the other stop body 46, so that reference can be made to the relevant description. However, for better differentiation, the reference symbols of the corresponding components are marked with an additional line.

In the area of the first slide section 26 upstream of the second adjustable stop 38', a further recess 65 is provided in which the associated counter stop 39', which is non-adjustably connected to the base housing 2, is arranged. This is located at the front end area 66 of the base housing 2 in order to ensure the greatest possible maximum stroke. It comprises a holding part 67, which is designed in particular as integral with the base housing 2 and projects into the further recess 65, which is provided with a continuous axial recess 57', for example, in which a counter stop body 56' designed in a similar way to the above description is seated. Its counter stop part 58' lies in the stroke path of the stop part 52' and thus limits the extension stroke.

As shown, the recess 65 can be covered on the top by a cover 70, which is expediently formed by a section of the slide 4. This makes it possible to provide a large and unjagged fastening surface on the top 34 of the first slide section 2β.

The second stroke limiting device 37 is further characterized in that its second adjustable stop 38' is designed as a structural unit with a shock absorber 68. For this purpose, the second adjustable stop 38' and in particular its stop body 46' can be formed by the cylindrical housing 69 of the shock absorber 68. It is preferably a fluidic shock absorber in which the damping effect is based on the displacement of a hydraulic or gaseous medium. Shock absorbers of this type are known as such, so that further explanations of how they work are unnecessary. In any case, Figure 3 shows a bumper 72 emerging from the front of the housing 69 with a bumper section 73 provided at the free end, which thus protrudes beyond the stop section 52' to the second counter stop 39'. When approaching the extended end position, the impact part 73 plunges into the buffer-free recess 62' of the counter-stop body 56' until it rests against the bottom thereof, so that during the further lifting movement the push rod 72 moves into the housing 69 and thereby causes the damping process which effectively brakes the slide 4. The damping process is completed when the housing 69 strikes the counter-stop part 58' with the stop part 52' provided on its front side.

If the second stop body 46' is adjusted for the purpose of changing the extended end position, this automatically results in an adjustment of the shock absorber 68, so that the damping stroke remains the same regardless of the end position set and a separate adjustment is not necessary.

The arrangement could also be such that the stop section 52' is formed by the impact section 53 and the end position is reached when the bumper 72 has covered the maximum damping path permitted by the shock absorber.

It should be mentioned that both stroke limiting devices 36, 37 can of course be equipped with or without a shock absorber 68. Conversion is possible at any time, since only the stop body and shock absorber need to be replaced. The buffer element 59 is also optional, although it is expediently omitted in conjunction with a shock absorber 68 as shown and can even be omitted in the case of a stroke limiting device without a shock absorber in the case of only low stroke speeds.

Claims (14)

G 17 886 - lens 20 March 1997 Festo KG, 73734 Esslincren Slide drive device Claims 1. Slide drive device, with a base housing (2) in which at least one actuating element (17) that can be driven for a linear movement is arranged, with a slide (4) arranged on the outside of the base housing (2) and coupled in motion to the at least one actuating element (17), which slide can be moved relative to the base housing by means of a guide device (18). (2) is guided linearly between two end positions, and with two between the base housing (2) and the slide (4) acting stroke limiting devices (36, 37) for the variable setting of the two end positions of the carriage (4), each of which has a arranged on one part, in the direction of movement (3) of the slide (4) adjustable stop (38, 38') and a counter stop (39, 39') arranged opposite this on the other part, characterized in that the one adjustable stop (38') on the slide (4) and the other the adjustable stop (38) is arranged on the base housing (2), wherein both adjustable stops (38, 38') are provided on end regions (42, 43) of the slide (4) or the base housing (2) pointing in the same axial direction. 2. Slide drive device according to claim 1, characterized in that the at least one actuating element (17) is designed as a fluid-loaded piston (6) which is connected to a piston rod (15) protruding from the front of the base housing (2) and fixed to the slide (4), the adjustable stops (38, 38') being located on the rear end regions (42, 43) of the base housing (2) and the slide (4). 3. Carriage drive device according to claim 2, characterized by a dual arrangement of piston (6) and piston rod (15), both of which are connected to the carriage (4). 4. Slide drive device according to one of claims 1 to 3, characterized in that the slide (4) has an L-shaped configuration, the slide section (26) corresponding to one L-leg axially overlapping the base housing (2) and being guided thereon, while the slide section (27) corresponding to the other L-leg protrudes in front of one end face (16) of the base housing (2) and is connected to the at least one actuating element (17). 5. Carriage drive device according to one of claims 1 to 4, characterized in that the carriage-side the counter stop (39') cooperating with the adjustable stop (38') on the axially opposite end region (66) of the base housing (2) and the counter stop (39) cooperating with the adjustable stop (38) on the base housing side on the facing end region (43) of the slide (4). 6. Carriage drive device according to one of claims 1 to 5, characterized in that the carriage (4) has, at its end region (43) facing the adjustable stop (38) on the base housing side, a recess (54) which is open at the front and preferably also at the side, into which the stop (38) can dip when the end position of the carriage (4) predetermined by it is reached. 7. Carriage drive device according to one of claims 1 to 6, characterized in that the carriage (4) has, at its end region (43) having the adjustable stop (38'), a recess (54') which is open at the front and preferably also at the side and which is axially delimited on the inside by a holding part (44') carrying the adjustable stop (38'), whereby the stop (38') can protrude into the recess (54'). 8. Carriage drive device according to one of claims 1 to 7, characterized in that when the carriage (4) is retracted, the two adjustable stops (38, 38') are approximately at the same height with respect to the direction of movement (3) of the carriage (4). 9. Carriage drive device according to one of claims 1 to 8, characterized in that the two stroke limiting devices (36, 37) are arranged laterally on both sides of the guide device (18). 10. Carriage drive device according to one of claims 1 to 9, characterized in that the carriage (4) axially overlaps the base housing (2), the guide device (18) running centrally along the carriage (4) and the base housing (2). 11. Carriage drive device according to one of claims 1 to 10, characterized in that the adjustable stops (38, 38') are formed by stop bodies (46, 46') having an external thread (45, 45') which are adjustably held in a threaded bore (47, 47') of a holding part (44, 44') provided on the carriage (4) or on the base housing (2). 12. Carriage drive device according to one of claims 1 to 11, characterized in that at least one stroke limiting device (36, 37) for dampening the impact of the carriage (4) when the predetermined end position is reached has a fluidic shock absorber (68). 13. Carriage drive device according to claim 12, characterized in that the adjustable stop (38, 38') and the shock absorber (68) associated therewith are designed as a structural unit. 14. Carriage drive device according to claim 13, characterized in that the adjustable stop (38, 38') is at least partially formed by the housing (69) of the shock absorber (68).